To make the sourdough starter: Combine the yeast, malt powder, and sugar
in the water and stir. Add flour and mix until the flour is hydrated.
Cover the bowl with plastic wrap and leave the preferment at room
temperature for 3 days. After 3 days you can choose to use the entire
starter or you can feed it and divide, saving the other half in a crock
(refrigerate) for future use. This stater can be used indefinitely as long
as you feed it or use it once every one or two months. To feed the starter
simply add another one and a half cups of flour and one and a half cups of
water. Allow to sit at room temperature for 24 hours, then divide saving
one half in the crock and either use the other half immediately or discard
it.

Add yeast and salt to the water in a 5-quart heavy-duty stand mixer bowl.
Don't worry about trying to dissolve the yeast. Add all of the flour at
once along with the entire preferment and begin mixing using a the dough
hook until the mixture is uniform. You're finished when everything is
uniformly moist, without dry patches. Kneading the dough is not necessary.
This step is done in a matter of minutes, and will yield a dough that is
wet and loose enough to conform to the shape of its container.

Transfer dough to a resealable, lidded plastic food container or
food-grade bucket. Allow the mixture to rise at room temperature until it
begins to collapse (or at least flattens on the top), approximately 2
hours, depending on the room’s temperature and the initial water
temperature. Refrigerate the dough, at this point, at least overnight
before using. Refrigerating the dough overnight makes it much easier to
handle.

When ready to bake your first loaf, prepare a pizza peel by sprinkling it
liberally with cornmeal or semolina to prevent your loaf from sticking to
it when you slide it into the oven. Sprinkle the surface of your
refrigerated dough with flour. Pull up and cut off a 19 ounce
(grapefruit-size) piece of dough, using a serrated knife. Hold the mass of
dough in your hands and add a little more flour as needed so it won't
stick to your hands. Gently stretch the top surface of the dough around to
the bottom on all four sides, rotating the ball a quarter-turn as you go.
The bottom of the loaf may appear to be a collection of bunched ends, but
it will flatten out and adhere during resting and baking. The correctly
shaped final product will be smooth and cohesive. The entire process
should take no more than 30 to 60 seconds.

Place the shaped ball on the cornmeal-covered pizza peel. Allow the loaf
to rest on the peel for about 90 minutes (it doesn't need to be covered
during the rest period). Depending on the age of the dough, you may not
see much rise during this period; more rising will occur during baking
(“oven spring”).

After 90 minutes, preheat the oven to 500 °F, with a baking stone placed
on the middle rack. Place an empty broiler tray for holding water on any
other shelf that won't interfere with the rising bread. Unless otherwise
indicated in a specific recipe, dust the top of the loaf liberally with
flour, which will allow the slashing knife to pass without sticking. Slash
a ¼-inch-deep cross,

After 30 minute preheat, you're ready to bake. With a quick forward
jerking motion of the wrist, slide the loaf off the pizza peel and onto
the preheated baking stone. Quickly but carefully pour about 1 cup of hot
water from the tap into the broiler tray and close the oven door to trap
the steam. Bake for about 5 minutes; then lower temp to 450 F and bake for
30 minutes or until the crust is nicely browned and firm to the touch.
Because you've used wet dough, there is little risk of drying out the
interior, despite the dark crust. When you remove the loaf from the oven,
it will audibly crackle, or “sing,” when initially exposed to
room-temperature air. Allow to cool completely, preferably on a wire
cooling rack, for best flavor, texture, and slicing. The perfect crust may
initially soften, but will firm up again when cooled.

Store the remaining dough in the refrigerator in your lidded (not
airtight) container and use it over the next 10 days: You'll find that
even one day’s storage improves the flavor and texture of your bread. This
maturation continues over the 14-day storage period. Refrigerate unused
dough in a lidded storage container (again, not airtight). Cut off and
shape more loaves as you need. The dough can also be frozen in 19 ounce
portions in an airtight container and defrosted overnight in the
refrigerator prior to baking day.

Recipe Notes

*Diastatic malt powder is available online. Or you could substitute 1/2 teaspoon of sugar in the starter.